Lyme disease is a bacterial infection transmitted by the deer tick. The deer tick can also transmit bacterial co-infections such as Bartonella, Babesia and Ehrlichia. The bacteria cause a myriad of arthritic and neurological symptoms, in addition to cardiac, or heart, functional abnormalities, according to the University of Maryland Medical Center.
Arrhythmia
Heart rate is naturally variable, rising during exercise and slowing during rest; however, when the heart rate is too fast or too slow and is stimulated to contract in an irregular manner, it is considered abnormal and is termed an arrhythmia. Lyme disease can cause arrhythmias that are typically not permanent once the Lyme infection is treated. Arrhythmias will cause rate irregularities, chest pain, breathlessness, unusual sensations in the chest, dizziness and fainting. The condition will start and stop suddenly and can occur during exercise or rest, according to Cedars-Sinai Hospital.
Heart Palpitations
Heart palpitations are irregular heartbeats with skipped intervals. The condition is accompanied by lightheadedness, fainting, breathlessness and chest pain. Palpitations are observed in the persons with Lyme disease, but are not dangerous, according to the Children's Hospital of Philadelphia.
Bradycardia
Bradycardia is a condition where the heart rate slows to less than 60 beats per minute. Some individuals can have a naturally low heart rate, particularly in athletes, but bradycardia is an atypical slow heart rate with adverse symptoms. Symptoms include dizziness, fatigue, weakness, fainting, chest pain and low blood pressure, notes the NYU Cardiac and Vascular Institute.
Heart Block
The heart contains four chambers: two atria and two ventricles. The chambers are made to contract in response to an electrical signal from the sinoatrial node, a bundle of nerve cells at the top of the heart. Heart block occurs when the signal is too slow, which causes the heart to contract slowly. It occurs in three stages. First degree heart block is asymptomatic and does not require any treatment. With second degree heart block, heart beats will be skipped, and a person may also experience fainting, chest pain, breathlessness and dizziness. Third degree heart block is severe and requires the surgical implantation of a pacemaker to regulate the heart. This condition is typically not permanent once the Lyme infection is addressed; however, permanent heart damage occasionally occurs, according to the Langone Medical Center.
Myocarditis
The heart is comprised of muscle called myocardium. Myocarditis is inflammation of the heart muscle. It is a rare Lyme disease complication that dissipates once the Lyme infection is treated. Myocarditis will cause chest pain, fatigue, fever, abnormal heart rate, joint pain, leg swelling and breathlessness, according to the University of Maryland Medical Center.
